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101.
We reviewed the experience at the University of Virginia over the past 10 years with renal tumors involving the inferior vena cava. There were 107 patients with renal tumors, 41 with invasion of the renal vein and 18 with involvement of the inferior vena cava. The groups with and without vena caval tumors were compared, and the operative approach is described. Although the rate of complications was higher in operations on the vena cava, none were fatal and no patient required chronic dialysis. Life-table analysis revealed that patients with involvement of the inferior vena cava survived longer than those with incomplete resection. Because extraction of these tumors can be accomplished with acceptable morbidity and mortality, because complete resection confers a survival advantage, and because chemotherapy and radiation are ineffective, we recommend aggressive workup and resection of renal tumors involving the inferior vena cava.  相似文献   
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The diagnostic value of aspirating blood clots while performing percutaneous biopsy of intramedullary lytic bone lesions was assessed. This was a retrospective analysis of 400 patients with intramedullary lytic bone lesions who underwent image-guided needle biopsy. The nature of the specimens obtained was noted from the histopathology records. In 83 (20.8%) of the 400 patients, the specimen obtained was either blood clot only or essentially blood clot with only tiny fragments of bone or soft tissue. Lesional tissue was present on needle biopsy specimens in 65 (78.3%) of the 83 cases, while in 18 (21.7%) cases no lesional tissue was obtained. In 24 of the 83 cases, there was no surgical histological diagnosis available. Inthe 59 cases where surgical histological diagnosis was available for comparison, the diagnostic accuracy for needle biopsy was 73%. Percutaneous biopsy provided the diagnosis allowing appropriate further management in 62 cases, for an overall diagnostic yield of 75%. The results of our study show a sufficiently good diagnostic value in obtaining blood clots as to necessitate routine attempts at obtaining such material while performing percutaneous biopsy of intramedullary lytic bone lesions.  相似文献   
105.
Neurodegenerative disorders are characterized by disruptions to neuronal function and circuitry,leading to a variety of clinical syndromes depending on the affected neuroanatomic regions(Geula,1998).Many proteinopathies implicated in neurodegenerative diseases are characterized by the pathologic accumulation of proteins into inclusions that are initially deposited in specific areas of the brain and spread widely with disease progression.  相似文献   
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(i) To determine whether neurology is the medical specialty with which Irish students and doctors have most difficulty, (ii) appraise attitudes towards how neurology is taught, and (iii) suggest ways teaching might be improved. A questionnaire on medical teaching was given to 457 medical students and junior doctors in Ireland. Perceived difficulties with neurology compared with seven other medical specialties were analysed. Other aspects of teaching were assessed including why neurology is perceived as difficult and ways teaching could be improved. Neurology was perceived as the most difficult of the eight medical specialties assessed. Participants felt they learned most at bedside tutorials with surprisingly few learning online. Neurology was perceived as difficult because of insufficient exposure to the subject, lack of teaching, and perceived complexity. Neurology teaching could be improved by increasing the number of bedside tutorials and by greater exposure to neurological patients for the students in clinical training. Medical students and doctors find neurology difficult. The teaching of neurology is reported as moderate to poor. The reasons for this are wide ranging but an emphasis on increased numbers of tutorials and greater integration of pre-clinical neurology to clinical years would improve teaching.  相似文献   
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Background:  The role of the autonomic nervous system in the complex link between insulin resistance and cardiovascular risk remains unclear. Increased sympathetic nervous system activity has been implicated in the pathophysiology of insulin resistance but is confounded by a number of factors.
Methods:  We have therefore examined the relationship among cardiac autonomic control, insulin resistance, habitual physical activity, resting energy expenditure (REE), and anthropometric variables in a subset (107 boys, 101 girls, age 9 ± 0.25 yr) of the EarlyBird cohort. Cardiac autonomic activity was assessed using time domain and power spectral density analysis methods of heart rate variability. Insulin resistance was measured using homeostasis model assessment of insulin resistance (HOMA2-IR).
Results:  Girls, in comparison to boys, showed significantly higher resting heart rate and lower systolic blood pressure (BP); were more insulin resistant; undertook less physical activity, and had lower fat-free mass and REE. Increasing fasting insulin and increasing insulin resistance were associated with increasing BP.
Conclusion:  The data suggest early gender differences in predictors of cardiac autonomic control. Pubertal staging was not undertaken in this study, and we plan to evaluate this in future studies to further clarify these associations.  相似文献   
109.
The promise of epigenome-wide association studies and cancer-specific somatic DNA methylation changes in improving our understanding of cancer, coupled with the decreasing cost and increasing coverage of DNA methylation microarrays, has brought about a surge in the use of these technologies. Here, we aim to provide both a review of issues encountered in the processing and analysis of array-based DNA methylation data and a summary of the advantages of recent approaches proposed for handling those issues, focusing on approaches publicly available in open-source environments such as R and Bioconductor. We hope that the processing tools and analysis flowchart described herein will facilitate researchers to effectively use these powerful DNA methylation array-based platforms, thereby advancing our understanding of human health and disease.  相似文献   
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